In 1860, Abbott declined an appointment to the Massachusetts Supreme Judicial Court, and in 1861 declined the Democratic nomination for state attorney general. He finally was victorious as a Democratic candidate for the United States House of Representatives, and served from July 28, 1876 to March 3, 1877. He was a member of the Electoral Commission created by the act of Congress approved January 29, 1877, to decide the presidential election of 1876.